Thursday, 9 October 2014

Objections against the fine-tuning argument-III

Objection: The key thrust of the argument from fine-tuning is that it is very improbable that the universe's conditions be "just right" to allow for our existence, and as such it calls out for an explanation. However, according to the weak anthropic principle, the universe's basic features must be conducive for the evolution of observers in order for them to observe the universe. In other words, were the basic features non-conducive to our existence, our existence wouldn't even be possible. But here we are. The fact of our existence entails that the initial conditions of the universe would be able to accommodate our existence in it. That's why the fine-tuning of the universe needs no explanation.

Response: This is one of the most common responses to the fine-tuning argument out there, popularized by (among others) Barrow & Tipler and Elliot Sober. I'm sure there are smarter formulations out there, but the basic thrust of the objection is completely, completely wrong-headed (although I've had to think quite a bit about the objection to understand it (and the response)). According to the objector, the fine-tuning proponent believes that it is the mere conduciveness of a universe to the observers' existence that requires explanation. But it is trivially true that it doesn't! This is the objection formalized:

1. If we exist, the universe's basic conditions would be such that allows our existence.
2. We exist.
3. Therefore, the universe's basic conditions would be such that allows our existence.

Everyone will agree with this. But once again, the mere "fit" between our existence and the universe's basic features is not what the fine-tuning argument holds to be surprising and requiring explanation. Rather, it is the peculiar way in which the fit occurs. Put differently, the conditions could be conducive of life in an infinite number of different ways. Of all these ways, a very peculiar, precariously improbable set of conditions is what yields life. Isn't that fact surprising? The laws and conditions could have been such that even if one were to vary them, it would have little or not effect on life. But that's not how things are- the conditions are very peculiar, such that even if you vary them a little, we would not have existed. The mere conduciveness is not what should surprise us as the objector things, but the peculiar nature of the conduciveness that should.

To understand this, consider the following illustration borrowed from Richard Swinburne:

Suppose that a madman kidnaps a victim and shuts him in a room with a card-shuffling machine. The machine shuffles ten packs of cards simultaneously and then draws a card from each pack and exhibits simultaneously the ten cards. The kidnapper tells the victim that he will shortly set the machine to work and it will exhibit its first draw, but that, unless the draw consists of an ace of hearts from each pack, the machine will simultaneously set off an explosion that will kill the victim, in consequence of which he will not see which cards the machine drew. The machine is then set to work, and to the amazement and relief of the victim the machine exhibits an ace of hearts drawn from each pack. The victim thinks that this extraordinary fact needs an explanation in terms of the machine having been rigged in some way. But the kidnapper, who now reappears, casts doubt on this suggestion. ‘You ought not to be surprised’, he says, ‘that the machine draws only aces of hearts. You could not possibly see anything else. For you would not be here to see anything at all, if any other cards had been drawn.’ But of course the victim is right and the kidnapper is wrong. There is indeed something extraordinary in need of explanation in ten aces of hearts being drawn. The fact that this peculiar order is a necessary condition of the draw being perceived at all makes what is perceived no less extraordinary and in need of explanation.

The conditions set by the kidnapper is analogous to the fine-tuning of the universe. It's true that the victim's survival entails the fact of conditions for her survival, but that's not what the surprising thing is- the surprising thing is that those conditions for the victim's survival is so peculiar and improbable in the first place. That's what requires explanation here.

I understand that the objection cannot be treated on its own, it opens up other important questions like:

1. Anthropic principle or no anthropic principle, why is the conditions being fine-tuned surprising at all, since every single outcome is equally probable?

2. What if the anthropic principle was conjoined with the existence of infinite (or at least a very, very, very large number) of universes? Surely that would render the fact of fine-tuning unsurprising, since someone has to win the lottery.

As for the first question, I will deal with it in a future post in sha Allah. As for the second, I sympathize with the objection. The response I've provided only works if the number of actual universes is just one (or a few). If there are an infinite or very large number of universes, then the anthropic principle objection becomes relevant again. The only way to deal with this problem is to deal with the multiverse, which I plan to do in a future post as well.

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